A computed tomography (CT) scanner includes an x-ray tube that emits radiation that traverses an examination region and a portion of an object or subject therein. A detector detects radiation traversing the examination region and generates projection data indicative of the detected radiation. A reconstructor reconstructs the projection data and generates volumetric image data indicative of the portion of the object or subject in the examination region.
Contrast media (e.g., iodinated agents) has been administered prior to scanning (a contrast enhanced scan) to improve tissue visualization during routine diagnostic imaging studies by CT, angiography, fluoroscopy, MRI and many other imaging modalities, interventional clinical procedures, therapeutic procedures such as percutaneous transluminal coronary angioplasty (PTCA), etc., and/or imaging procedures. The literature has indicated tens of millions of radiologic examinations using iodinate contrast media are performed each year.
Generally, a large volume of contrast media results in higher contrast to noise ratio (CNR) images, while a lower volume of the contrast media leads to lower CNR images. Unfortunately, as the contrast media volume increases, so does its associated risks. By way of example, after parenteral administration of a contrast media, many patients experience idiosyncratic effects, such as warmth, nausea, itching and other types of effects. Certain patients may experience severe and potentially life-threatening allergic reactions to contrast media. Contrast media may also induce kidney damage (contrast Induced Nephropathy (CIN)) as some patients may develop an acute deterioration of their kidney function due to the fact that iodinated contrast media is cleared via the kidneys.
As the amount of contrast media delivered to a patient is a concern, a set of technological enablers have been developed to reduce contrast media usage. Examples of such enablers include electronically controlled injection devices, high rate chaser saline, faster rotation time, wider coverage area, bolus tracking software and the use of low kV protocols. Furthermore, non-ionic and low osmolar agents have been developed, which are better tolerated by patients with regard to idiosyncratic effects, but generally are more expensive. However, there is an unresolved need for novel and non-obvious approaches that facilitate reducing the amount of contrast media utilized for scanning patients while providing diagnostic quality images.